Solved Question Paper of Recruitment Test (Computer Based Recruitment Test) conducted by UPSC for the Post of Deputy Controller of Explosives in Petroleum and Explosives Safety Organisation (PESO) held on 29.07.2018.
 
1. The condition of stable equilibrium for a floating body is:
(a) The metacentre M coincides with the centre of gravity 𝐺
(b) The metacentre 𝑀 is below the centre of gravity 𝐺
(c) The metacentre 𝑀 is above the centre of gravity 𝐺
(d) The centre of buoyancy 𝐵 is above the centre of gravity 𝐺

Answer: (c)

2. For a submerged curved surface, the vertical component of the hydrostatic force is:
(a) Mass of the liquid supported by the curved surface
(b) Weight of the liquid supported by the curved surface
(c) The force on the projected area of the curved surface on vertical plane
(d) Centriod of the liquid displaced by the body

Answer: (b)

3. The least radius of gyration of a ship is 8 m and metacentric height is 70 cm . Then the time period of oscillation of the ship is nearly:
(a) 19.2 s
(b) 17.4 s
(c) 15.6 s
(d) 13.8 s

Answer: (a)

4. The flow of water leaving the impeller in a centrifugal pump casing is:
(a) Forced vortex flow
(b) Free vortex flow
(c) Centrifugal flow
(d) Centripetal force

Answer: (b)

5. A mouthpiece is a short length of pipe fitted to a tank containing fluid. Which one of the following mouthpieces is having a maximum coefficient of discharge?
(a) External mouthpiece
(b) Convergent-divergent mouthpiece
(c) Internal mouthpiece
(d) Cylindrical mouthpiece

Answer: (b)

6. Hydraulic Gradient Line (HGL) is the sum of:
(a) Pressure head and kinetic head
(b) Kinetic head and datum head
(c) Pressure head, kinetic head and datum head
(d) Pressure head and datum head

Answer: (d)

7. Three pipes of length 800 m, 500 m and 400 m and a diameter of 500 mm, 400 mm and 300 mm respectively are connected in series. These pipes are to be replaced by a single pipe of length 1700 m, and then the diameter of the single pipe should be nearly:
(a) 324 mm
(b) 344 mm
(c) 372 mm
(d) 412 mm

Answer: (c)

8. 
(a) 83.4 mm
(b) 86.3 mm
(c) 89.2 mm
(d) 92.1 mm

Answer: (d)

9. 
(a) 3
(b) 4
(c) 5
(d) 7

Answer: (a)

10. The thermal conductivity (𝑘) of insulators:
(a) Increases with increase in temperature
(b) Always increases with increase in the density of the material
(c) Decreases with increase in temperature
(d) Decreases due to convection phenomenon in insulators

Answer: (a)